This invention relates to a device for coupling a submarine conduit to another conduit of a pipe-line or fixed installation, the submarine conduit being at least temporarily maintained in hydrostatic equilibrium by a lightening system such as floats, etc.
In theory, the connection of a submarine conduit to another conduit, of a pipe-line or storage tank for example, does not present any problems. However, in practice, certain problems do arise. In fact, despite all the precautions taken, it frequently happens that variations occur with regard to the planned direction and distance. Variations regarding direction only present slight disadvantages, but the variations in distance are more serious. If, for example, the conduit is intended to connect a well to a storage tank, then the tank, which is a large volume construction sometimes having to be submerged at considerable depth, cannot be positioned with any great precision from the surface. To overcome these disadvantages, U.S. Pat. application Ser. No. 886,061, now U.S. Pat. No. 4,254,728, proposes a coupling device which makes it possible to moor the end of a submarine conduit at an exactly defined distance in relation to the end of another fixed conduit and to connect the ends of the two conduits by a standard connecting pipe.
The known device comprises a mooring frame resting on the sea-bed on which a mooring arm is arranged which can be rotated in a horizontal plane. The end of the fixed conduit is secured on the axis of rotation of the arm. The arm, at its movable end, comprises a hollow cylindrical portion leading to a conical portion which cooperates with a mooring head fixed to the end of the conduit which is to be connected.
The mooring head comprises a partly cylindrical body fixed to the end of the conduit on its axis, and having a lateral passage through which the end of the conduit may extend, releasable means for attaching the mooring head to a towing cable, means for securing the mooring head to the rotatable mooring arm, and positioning means fixed on to the cylindrical body in such a way as to predetermine the angular position of the end of the conduit to be connected in relation to the perpendicular.